In many industries that handle gaseous materials, considerations such as efficiency improvements and health and safety requirements are leading to increasing demands on gas leak detection technology. Examples of applications where detecting leaks is critical include butane fill lines at aerosol plants and natural gas pipelines, where the safety implications of a leak are self-evident.
In prior art leak detectors, the presence or concentration of a leaking gas is directly detected or measured by one of a variety of techniques such as photo-ionisation, flame ionisation, photo acoustic effects or infra-red (IR) absorption. These techniques have several disadvantages, including the need to produce and purchase a dedicated detector for each gas used. In addition, some gasses are inherently unsuitable for use with certain detection techniques, because they do not strongly adsorb infrared radiation or they absorb in a region masked by other materials having stronger absorbing characteristics.